The invention relates generally to cutting inserts and, more particularly, relates to a double-sided, trigon cutting insert with three major cutting edges, three rounded minor cutting edges and three planar peripheral side surface portions and a cutting tool with an insert-receiving pocket having three planar side support surfaces for supporting the three planar peripheral side surface portions.
One skilled in the art understands that a roughing operation or rough-machining operation is a machining operation that produces a rough surface on a workpiece, and that a finishing operation or finish-machining operation is a subsequent machining operation of the rough surface generated by the preceding rough-machining operation that produces a fine finish on the workpiece.
One example of a finishing cutting insert is a cutting insert having a hexagonal base body with cutting edges that are alternately designed as finishing cutting edges and roughing cutting edges. The roughing cutting edges are called major cutting edges and the finishing cutting edges are called minor cutting edges. On a surface milling cutter, several roughing inserts for rough-machining are distributed along the front-face periphery of the surface milling cutter, while several finishing inserts for finish-machining are arranged at predetermined locations.
There is also an example of an existing cutting insert with an octagonal geometry in which each of the eight lateral edges has one finishing cutting edge and one roughing cutting edge. For this purpose, the individual cutting edges are arranged at different levels, i.e., they do not lie in the same plane. For each cutting edge, an inclined cutting face is radially adjacent to the center axis of the cutting insert, so that the surface topography of the cutting insert is very complex.
When machining a workpiece with a surface milling cutter, for example, there is a problem of higher feed speeds in which the machined surface has an insufficient surface quality with bumps in the shape of an arc of a circle.